Oregon Revised Statutes Water Resources: Irrigation, Drainage, Flood Control, Reclamation § 547.250

(1) The board of supervisors, for and in behalf of the district, or the owners of land adjacent to the district, may file a petition in the office of the clerk of the court which organized the district, praying the court to amend its former judgment incorporating the district, by correcting the names of landowners, by striking out any such names, by adding, striking out or correcting the descriptions of any lands within or alleged to be within the boundary lines of the district, or in any other manner.

(2) The petition may ask permission of the court to amend or change the plan for reclamation or to correct any errors, omissions or other mistakes that have been discovered in the plan or may ask that the boundary lines of the district be extended so as to include lands not described by and included in the petition and judgment of the court incorporating the district. However, in no case shall any lands be included in the district other than the lands described in the original petition for the creation of the district and in the judgment of the court incorporating it, unless the persons shown by the records of the county to be the owners of not less than 60 percent of the acreage sought to be brought within the boundary lines of the district and not described in and included in the original petition and judgment of the court incorporating such district, shall first sign and file with the court a petition therefor.

(3) If the petition asks that the lines of the district be in any manner changed, it shall also ask the court to appoint three commissioners, as provided for under ORS 547.215, to appraise the land that shall be taken for rights of way, holding basins, or other works, or assess the benefits and damages to any lands, public highways, railroad and other property already in the district, or that may be annexed to the district by the proposed amendments and changes to the plan for reclamation or the proposed change in the boundary lines. As soon as the petition is filed the clerk of the court shall give notice in the manner and for the time provided for in ORS 547.020, the notice to be substantially in the following form: